One vertex per element, one color per generator, with an edge from x to x·s.
(5,6)(7,11)(8,9)(10,12)(13,14)(15,22)(16,21)(17,20)(18,24)(19,23)(25,28)(26,27) involution — undirected(1,2)(3,4)(6,9)(10,11)(14,20)(15,16)(18,19)(21,28)(22,27)(25,26) involution — undirected(13,15,17,25)(14,21,20,27)(16,18,26,19)(22,23,28,24)(2,4)(13,16)(14,22)(15,18)(17,26)(19,25)(20,28)(21,23)(24,27) involution — undirected(5,7,8,12)(6,10,9,11)(14,20)(21,27)(22,28)(23,24)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.